Data communication services are essential in present day network communications systems. While many services, such as networked applications sharing common files and internet web browsers, generally require a bidirectional communication interface, many data services operate for the most part as a uni-directional service. Examples of such services are file transfers of large blocks of data such as weather map information, position, vector and course information from other mobile users, airport ground information, and audiovisual entertainment.
A critical point in providing or receiving data services is the ability to connect to the network. In present day network systems, it is not necessary for each user to connect directly to the network. Rather, users typically connect remotely to the network via modem by dialing a conventional telephone number of an access point. The access point is typically a switch owned by a network service provider through which remote callers are authenticated as authorized users and then connected to the network. One difficulty in present networked systems is the ability to maintain a network connection, either directly or remotely, when a user is mobile. Most local communications networks are ground based and use line of sight (LOS) communications links. These types of communication systems work well when each node in the communication network is stationary. However, if a network node is mobile, as for example an airborne aircraft or a mobile ground equipment vehicle, the ability to maintain a connection to a communications network becomes more difficult, especially where the mobile user travels far distances or across several geographical boundaries. This occurs because the mobile user moves in and out of range of any single ground based communication system. Furthermore, even in cellular radiotelephone communications system, which provide communication links for moving subscriber units, the ground based switching centers, or "cells", must each be in communication and are required to conduct a lengthy subscriber authentication processing order to service a "roaming" subscriber unit that is out of range of its "home" cell but which is within the range of control of a "visited" cell. This results because only the home cell of a subscriber has full access to its authentication information (e.g, the subscriber unit identifier (ID) which uniquely identifies the subscriber unit from other subscriber units). Accordingly, the overhead involved in sending a message is quite high, impractical, and even impossible when the subscriber moves out of range of any cell in the cellular network. Furthermore, subscriber units of cellular based communication systems are not set up to handle large blocks of incoming data at high speeds. In addition, in order to send data from one node in a communication network to another, the location of the destination network node must be known. Where a subscriber travels in and out of the range of communication of several ground based communication systems, the location of the subscriber unit is always changing and hence not necessarily known. Accordingly, it is very difficult to send data, and especially large blocks of high-speed high-bandwidth data, to mobile users in a communication system.
What is needed is a system and method for providing timely delivery of large blocks of digital data on a one-way as-needed basis from a data information service provider to a mobile user.